The Highlanders

From http://www.bbc.co.uk/doctorwho/classic/episodeguide:

The time travellers arrive in Scotland in the aftermath of the battle of Culloden. The Doctor gains the trust of a small band of fleeing Highlanders by offering to tend their wounded Laird, Colin McLaren; but while Polly and the Laird's daughter, Kirsty, are away fetching water, he and the others are all captured by Redcoat troops under the command of Lieutenant Algernon ffinch.

Grey, a crooked solicitor who sells prisoners for transportation to slavery in the West Indies, then secures the group into his custody. Polly and Kirsty blackmail ffinch into helping, and the Doctor eventually wins the day by smuggling arms to the Highlanders, who are being held on board a stolen ship, the Annabelle.

Grey and the ship's unscrupulous captain, Trask, are overpowered and the vessel returned to its rightful owner, MacKay, who agrees to take the Scots to safety in France.

The Doctor, Polly and Ben return to the TARDIS, where they are joined on their travels by the young piper Jamie McCrimmon.

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